Method and Apparatus for Radio Resources Management in Multi-Radio Access Technology Wireless Systems

1. A wireless transmit/receive unit (WTRU) comprising: a transceiver and a processor configured to establish a connection with a first cell of a first radio access technology (RAT), wherein the WTRU communicates radio resource control (RRC) information having a first RRC format of the first RAT using a first signaling radio bearer (SRB); the transceiver is further configured to receive from the first RAT a RRC reconfiguration message including a container having configuration information for a second RAT, wherein the configuration information for the second RAT includes establishment information for a second SRB, wherein the first RAT and the second RAT are different RATs; and the transceiver and the processor are configured to communicate using both the first RAT and the second RAT.

2. The WTRU of claim 1 , wherein the WTRU communicates RRC information having a second RRC format of the second RAT and wherein the first RRC format and the second RRC format are different RRC formats.

3. The WTRU of claim 2 , wherein the processor is further configured to distinguish between the first RRC format and the second RRC format based on a received SRB identification (ID).

4. The WTRU of claim 2 , wherein the processor is further configured to determine that a reconfiguration procedure for the second RAT is initiated based on a determination that RRC information having the second RRC format is included in the RRC reconfiguration message having the first RRC format.

5. The WTRU of claim 1 , wherein: the processor is further configured to establish a second medium access control (MAC) entity for the second RAT, in response to the received RRC reconfiguration message, wherein the first RAT has a first MAC entity; and the transceiver and the processor are configured to communicate using both the first MAC entity and the second MAC entity.

6. The WTRU of claim 1 , wherein a single RRC state is used for both RATs.

7. The WTRU of claim 6 , wherein a single RRC instance and a single RRC state machine is used for both the first and second RAT.

8. The WTRU of claim 1 , wherein the first RAT is long term evolution.

9. The WTRU of claim 1 , wherein a first WTRU identity is associated with the first RAT and a second WTRU identity is used for the second RAT, wherein the WTRU uses the first identity for communications from the first RAT and the second identity for communications from the second RAT.

10. A method performed by a wireless transmit/receive unit (WTRU) comprising: establishing a connection with a first cell of a first radio access technology (RAT), wherein the WTRU communicates radio resource control (RRC) information having a first RRC format of the first RAT using a first signaling radio bearer (SRB); receiving from the first RAT a RRC reconfiguration message including a container having configuration information for a second RAT, wherein the configuration information for the second RAT includes establishment information for a second SRB, wherein the first RAT and the second RAT are different RATs; and communicating using both the first RAT and the second RAT.

11. The method of claim 10 , wherein the WTRU communicates RRC information having a second RRC format of the second RAT and wherein the first RRC format and the second RRC format are different RRC formats.

12. The method of claim 11 , further comprising: distinguishing between the first RRC format and the second RRC format based on a received SRB identification (ID).

13. The method of claim 11 , further comprising: determining that a reconfiguration procedure for the second RAT is initiated based on a determination that RRC information having the second RRC format is included in the RRC reconfiguration message having the first RRC format.

14. The method of claim 10 , further comprising: establishing a second medium access control (MAC) entity for the second RAT, in response to the received RRC reconfiguration message, wherein the first RAT has a first MAC entity; and communicating using both the first MAC entity and the second MAC entity.

15. The method of claim 10 , wherein a single RRC state is used for both RATs.

16. The method of claim 15 , wherein a single RRC instance and a single RRC state machine is used for both the first and second RAT.

17. The method of claim 10 , wherein the first RAT is long term evolution.

18. The method of claim 10 , wherein a first WTRU identity is associated with the first RAT and a second WTRU identity is used for the second RAT, wherein the WTRU uses the first identity for communications from the first RAT and the second identity for communications from the second RAT.